With constant development of current large data era, a stacked storage system has been applied increasingly wider. The stacked storage system always involves multi-layered components. A multi-layer structure makes it hard to perform I/O performance analysis and adjustment to the storage system. Moreover, when the stacked storage system is specifically deployed in an application, the storage system may receive various kinds of I/O requests generated by the application. However, the performance of the stacked storage system sometimes cannot support a specific application scenario. In most cases, such specific application scenario is not allowed to be reproduced at a client. This also makes it hard to perform analysis and adjustment to the I/O performance of the stacked storage system.